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#include <iostream>
#include <queue>
#include <vector>
using namespace std;

void bfs(vector<vector<int>> &G, int s) {
    vector<bool> visited(G.size(), false);
    queue<int> q;                              

    q.push(s);
    visited[s] = true;

    while (!q.empty()) {
        int node = q.front();
        q.pop();
        cout << node << " ";   

        for (int neighbor : G[node]) {
            if (!visited[neighbor]) {
                q.push(neighbor);
                visited[neighbor] = true;
            }
        }
    }
}

int main() {
 
    int e,x,y;
    cin>>e;

    vector<vector<int>> G(e);

    for(int i=0; i<e;i++){
        cin>>x>>y;
        G[x].push_back(y);
        G[y].push_back(x);
    }

    bfs(G, 0);

    return 0;
}